Chinese Journal of Catalysis ›› 2023, Vol. 47: 171-180.DOI: 10.1016/S1872-2067(23)64397-9

• Article • Previous Articles     Next Articles

Vinylene-linked covalent organic frameworks with manipulated electronic structures for efficient solar-driven photocatalytic hydrogen production

Zhipeng Xiea,1, Xiubei Yangb,1, Pei Zhangb, Xiating Kea, Xin Yuanb, Lipeng Zhaib,*(), Wenbin Wanga, Na Qinb, Cheng-Xing Cuic,*(), Lingbo Qud, Xiong Chena,*()   

  1. aState Key Laboratory of Photocatalysis on Energy and Environment, Key Laboratory of Molecule Synthesis and Function Discovery (Fujian Province University), College of Chemistry, Fuzhou University, Fuzhou 350116, Fujian, China
    bHenan Key Laboratory of Functional Salt Materials, Center for Advanced Materials Research, Zhongyuan University of Technology, Zhengzhou 450007, Henan, China
    cSchool of Chemistry and Chemical Engineering, Henan Institute of Science and Technology, Xinxiang 453003, Henan, China
    dCollege of Chemistry, and Institute of Green Catalysis, Zhengzhou University, Zhengzhou 450001, Henan, China
  • Received:2022-10-19 Accepted:2023-01-16 Online:2023-04-18 Published:2023-03-20
  • Contact: *E-mail: zhailp@zut.edu.cn(L. Zhai),chengxingcui@hist.edu.cn(C.-X. Cui),chenxiong987@fzu.edu.cn (X. Chen).
  • About author:1Contributed equally to this work.
  • Supported by:
    National Natural Science Foundation of China(21972021);National Natural Science Foundation of China(52103277);Key Projects of Science and Technology of Henan Province(212102210208);Key Projects of Science and Technology of Henan Province(202102210054);Key Projects of Science and Technology of Henan Province(212102210442);Zhongyuan University of Technology Start-Up Grant and the Independent Innovation Application Research Project(K2020YY001)

Abstract:

Vinylene-linked covalent organic frameworks (COFs) are promising photocatalysts owing to their fully conjugated skeletons that facilitate charge carrier mobility. Constructing donor-acceptor (D-A) architectures could further enhance photoinduced charge generation and transport, thus promoting photocatalysis. Therefore, three D-A-type vinylene-linked COFs were fabricated via Knoevenagel polymerization for efficient photocatalysis. By varying the donor moieties from phenyl to 2,5-dimethylbenzene and 3,3'-dimethyl-1,1'-biphenyl in the skeletons, the light-harvesting, optical-bandgap, and charge-transfer properties of the COFs were precisely regulated. All three COFs exhibited attractive photocatalytic hydrogen evolution rates (HERs) upon visible-light irradiation, especially that fabricated using 2,4,6-trimethyl-1,3,5-triazine (TM) and 3,3'-dimethyl[1,1'-biphenyl]-4,4'-dicarboxaldehyde (DMA, TM-DMA-COF). TM-DMA-COF exhibited the strongest D-A interactions, excellent charge-carrier separation and transfer kinetics, and a reduced energy barrier for H2 formation. Thus, it afforded the highest HER of 4300 µmol h‒1 gcat‒1, surpassing those of most state-of-the-art COF photocatalysts. This study provides a simple and effective protocol for modulating the photocatalytic activities of COFs at the molecular level and an interesting insight into the relationship between structural design and photocatalytic performance.

Key words: Covalent organic framework, Photocatalytic H2 generation, Olefin linkage, Porous polymer, Donor-acceptor